Vacuum fuel-feeding system



Dec. 26, 1922.

W. O. CHASE.

vAcuuM FUEL FEEDING SYSTEM.

FILED iUNE 11, 1921.

44444 444 4 444414444444444 4 44414 il. \k\\ Patented Dec. 26, 1922.

UNITED STATES WILFRED 0. CHASE, OF BEDFORD, MICHIGi'l, ASS' i SPEEDMETER CORPGRATION, 0]? CHCAGG, ILLIIM, ik

PATENT OFFICE.

` .EPURATION l VACUUM; FUEL-FEEDNG ffii.

Application filed .Tune 11, 1552i.

To utf/ yifa/tom t may concern:

Be it known that I7 VILFRED O. CHASE, a citizen of the United States lof America, residing at Redford, in the county of Vayne and State of Michigan, have invented certain new and useful Improvements in Vacuum Fuel-Feeding Systems, of which the following is a specification, reference being had therein to the accompanying drawings.

The invention relates to vacuum fuel feeding systems for use upon motor vehicles and consists in the novel construction as hereinafter set forth.

in the drawings:

Figure l is a vertical central section through the tank;

Figure 2 is a similar view of the upper end of the tank showing the valves in a different position of adjustment.

In the present state of the art vacuum fuel feeding systems applied to motor cars are generally provided with a vacuum tank arranged above the level of the main fuelholding tank and having two compartments, one for containing fluid .vlrffh is fm directly to the carburetor and the other heing connected with the main tank and alternately connectedwithv the source of vacuum and with an air vent, wherehyfuel is rst drawn up from the main tank into one compartment and then permitted to discharge into the other compartment. The source of vacuum in the intake manifold of the engine in which, when the throttle is closed or partly closed, there is a comparatively high vacuum. This Vacuum is communicated to the suction compartment of the tank, lout it is obvious that the air within this compartment must be drawn out and discharged into the manifold before it can he replaced hy the liquid from the main tank. The air so discharged having been previously in Contact with the liquid fuel is ciubureted., but as the proportion of the mixture s not generally right for explosion, it is obvious that the character of the mixture fed to the engine cylinders will he more or less .affected thereby., This nurticularly true where the engine is idling and onlj,v -a small quantity of carbureted air is drawn past the throttle, so that there is danger of stalling of the engine by the mixture drawn from the tank. To avoid Serial No. e745,

the past to reduce to the minimum theA volume of carbilreted air drawn through the vacuum connection, lout this has introduced other diflicuites. Thus, Where the 'le is running at' high speed and the hottie is wide open, the vacuum in the intake is comparatively low and if this condition is long continued, there may be a faiiure to supply sufficient fuel for the operation of the car.

lt is one of the features of the present' invention to provide means for varying the area of the vacuum connection to the tank. Vlhis is so arranged that when the vacuum 'ld high, the engine oeingiidling or running at low speed and requiring a small quantity of fuel, the vacuum connection is restricted. This will prevent interference with proper carlouretion by limitin the volume of carhureted air drawn from the vacuum tank. 0n the other hand, 'when the vacuum in the manifold is low, as Vwhere the throttle is open and the engine is running` high speed and usingk a larger quantity of fuel, the restriction to the vacuum connection is removed sothat alarger area is open for the more rapid witlnlrawal of air` from the vacuum chamher and the faster feeding of the fuel.

Another important feature of my imprrw'enient is the 'pneumatic operation ofthe valves which control the Vacuum tank. This not only simplifies the construction, but renders it more sensitive and quicker in response than mechanically operated controis. v

In detail, A is the vacuum tank which at its upper end is provided with an inner tank B forming the vacuum chamber and leaving an annular space C between the saine and the walls of the outer tank A. D is a head for closing the tank and which is suitably manila-neel for the reception of the rontroliing Yalves and various connect' Within the inner tank B is a ioat 's fixed upon a stem F slidahly enride hearings and H. The upper u a Valve I for end controlling a channel K.,

connected hy a nipple L to the cor init leading to 'the intake manifold. The valve I is engaged with its seat upon the rising of the float E to a predetermined point, thereby cutting olf the vacuum connection. On the other hand, when the iloat lowers to a predetermined point, it will draw the stem downward, withdrawing the valve I from its seat and opening the vacuum connection.` It is necessary to open and close an air vent connection to the tank B respectively upon the closing and opening of the valve I and this is pneumatically operated by the following construction:

0 is a gravity seated valve which controls a coi'inection between the channel l and other channel. P, which leads to a valve Q, This valve is so constructed that when the channel "lD is in communication with, the suction channel K, the valve tl, will be drawn to a seat ll, which seals thel channel l, and said valve will also'be liilted away from a seat S c'ontrolling,` an air rent 'l to the cliamber in the tanlrl. The valve is lifted from its seat by an 'upward projection ll on the stein F and the arrang ment is such that when the valve il is forced to its seat, the valve U will be unseated and by opening` the channel P to the vacuum will litt the valve Q engaging it with its seat ll and withdrawing it from its seat il, 'lhis will simultaneously cut oil rthe vacuum ill-om the chamber B and-' open up an air `vent thereto.

They chamber within the tanlr B has a discharge connection into the tanl; il, which. is controlled by a check valve "ll", said va f automatically opening` I by the hydrostatic pressure of 'the liquid above the same and closing when vacuum within the chamber B removes such pressure. There is also pro vided a yent connection "7V betwee-:i the chamber in the outer tank il and the channel VV which connects with, the vent port '.l`, so that whenthe valve Q opens the port T, air communication is establishedv between the chamberv in the tank l and that in the tank will eut the air vent T, so that atmos` pheric pressure within the chamlcr can be lowered to that existing` within the inaniold of the engine. ythis will l the liquid fuel from the main tank dischargri it throufrh the nr inle intothe chamber B until the rising` of the 'lloat lll to the pre r` mined point will seat the valve l. lhf ing ofthe stein will ca se the upwarc extension ll thereof to unseat the `i'alve l), establishing vacuum connection between the nipple-L and the channel lla and thereby lilting lis has been stated, one of the eaturesol my improvement the variable restriction in the vacuum connection corresi'ionding to variations of vacuum in the intake n'n'inilold and variations in speed o1"l power of the engine. rlhis isaccoinplishcd by tapering),a the upward extension ll of the stein F so as to 'loim thereof a metering` pin 'lor variably rf-istricting` the port opening el the channel l. l/Vhen the e. gine is idling, the high vacuum in the intake manifold will be communicated to the channel li, but the restriction caused by the metering; pinll will linut the quant-ity ci. air that can. be drawn through the port. rlhis will avoid intel-:terence with the operation ol the engine by introduction oil too great a volume ci air from the vacuum tank. Under the conditions just described the metering pin is not withdrawn to enlarge the opening, for the reason that the l'loat does not drop below its predetermined level at which the valves are reversed and suction is placed in the chamber B. This is because the high vacuum in the intaire manifold will, even. through the restricted port, withdraw the air and lill the chamber `with liquid Ylaster than it is beingr withdrawn from the lower chamber in teedl ing;` to the carburetor. lil", on the other hand,

the throttle open and the engine is oper? ated at high speed, this will decrease the vacuum in the manifold and greatly increase the demand for liquid fuel. Consequently, the liucl will be withdrawn from the lower compartment faster than it is being supplied from the upper compartment and as the two compartments are periodically 4ilaced in coiinminication, the level of the l'luin in the upper compartment will drop below itsI normal l'loat level. VThis permits the at to c oi dro p, thereby wi 'th/dra win '1 spondingy the ieterinp; in ll and enlaiigin,gf` tla port openi i to the channel This intern will increase the volume oil an.' that is'withdrawn iii-ein the upper chamber so as to soon .crinen about a state ci? balance fliere the nount ot liquid pumped by the tank is equal to that being' led to the el "buretor To render this operation more certain, l bij; prov'de Vncans :tor permitting,` the Y :cation ol Y ,qu levels in 'the tr i partments even where the vacuum is placed on the upper compartment. This consists CIK `tlnpugn the port Z.

`the eheolr valve.

in a bleed port Z, preferably :in the bottoni oi" the compartment B and Laloove the level of disifharge through the oiieel; valve V. 'lhe port Z is controlled hy a eheelr valve 5L", which is normally open, hut is Closed when vacuum is placed on upper coni pertinent by the velocity ol liquid passing A li", on the other hand7 the Withdrawal ot the liquid Vifuel troni the lower ton-l; is in excess oi the supply troni the upper compartment, the level in the lower compartment Will drop heloiv that of Also, the loiv vaeuuni in the intake manifold lwill onli7 Withdraw the air slo'xvl troni the upper compartment so that the oree acting to close the Cheek valve Z is insu'llieient. Consequently, the bleed port Z is lelt open and air lroni the loiver Compartment can pass upward through the liquid in tne upper ooinpartinent7 permit tintey the continued diseharge troni the upper to the lower eoinpartnient until either the liquid is eonipletely Withdrawn 'from the tipp-,r compartment or is equalized in level that ol the lower eonipartrnent. This, as heifore suitedy will withdraw the metering pin U and will thereby increase the port opening to the Channel l and correspondingly increase the wit drawal ot air .trein the upper compartment and the ieeding in the liquid. lnotlier Ali'iiiotion that is perlorined by the eheelr valve Z and port Z is to automatically perniit the Afeeding oil liquid lroin the upper to the lower Comparo nient whenever there is e.. ten'iporary liailure oit vaeuurn in the upper ooinpartnient, due to pulsations ol the engine when the throttle is lavide open.

'lhe upper level ol liquid in the upper compartment is determined by the vaouuin in the ohainher and the area oit the valve O exposed to said vaeuuni balanced against the buoyancy ol the iloat. lt will he understood that the valve O when seated is exposed to etinospherio pressure on its upper side, ano therefore, to litt it frein its seat, the differential het-Ween atmospheric and the vacuum pressure inust he overcome. Thus when the level ot liquid in the upper eoinparti'i'ient is risinge the lloat will oe lifted until the en e sion il hears against the valve @j but nrt-her rise is prevented until sutiiifient presnre developed to overcome the differential ir pressure on the val e (l. f llliereiiore, hy };.roperly proportioning the olf the valve l), any desired npperflevel of liquid inay loe ostahlished.

I'lhe mechanical construction ol' niy iniproved tana. ver;v simple and :is shown in detail the various ports and passages are 'fr med hy hores in the heads l). The chainlier the 'valve is elosed hy a cap which inayhe easily removed to obtain access to said valve. llo the seat lilor the valve Qi xorined f" t niay lie renioved to obtain aeeess to this valve.

l7l7hat l olaini as iny invention is:

l. Tn a vaeuuin tank7 oon'ipurtinent provided with a liquid s .pply eonneetionand a vnruun'i Connection, a t: lat in said Coinpertinentj a valve actuated hy the rise ot said float to out oli sai l vacuum connection, seoond valve held to its seat oy the dillo ential pressure el the vaeuuni und atmospheric pressure-sa second valve opposing) the seating of seid l'iret va.. the rising; olf the doet@y and ineens pneunnitieally operA ated upon the unseating ot said lestai'ientioned valve vtor oiieiiinn' a vent to said coinpertinent.

f. ln a vaeuuni tank, a compartment provided with, a liquid supply eonneetioin a vae-noni connection and a check valve oontrolled liquid discharge oonneetioin a lioat 'd oonipartineni7 valve directly aetuated hy tlm" elE said floot to ont oli' said vaouiini e nneetion, a valve held to its seat by dill'ierentinl pressure oil the vaouuin and atinosph' re and a stop opposing the said iirst-nientioned valve and the float, a valve loi' closing` an air vent to said eonrpartnient, and means for unseating said le tnientioned valve by the vaouuin rendered eileotive on the unseatingr oit said se:ond-mentioned valve.

ln a vaeuuni tanlr a compartment provided with a liquid supply connection, a vaeuuni oonneotion and a eheok valve Controlled lioiuid disoharge passagen a tloat in said eoinpartinent, a stein on whioh said 'float is sleeved, a valve on said stein 'tor Closing; said vaouuni connection, an extension ol said stein beyond said valve, a volvo in the path o'l" said extension held to its seat by the dillerential of atniospherie and vaouuin pressures and opposing the closing of said nist-mentioned valve and rise olf said float until a jipiredeterniined liquid level is attained a valve oontrolling,` an nir vent to said compartment having a portion exposed to .e'iential pressure upon the unseating olf said second-mentioned valve by which said last-mentioned valve is raised troni its seat and held over until the reseatingof said second-mentioned valve.

ln a voeuuin tank, compartment provided with a liquid supply oonneetioin a 'vacnuni ooinieetiorny :i eheok valve controlled discharge passage und :in air vent port, a lloat in said rhainlier, a valve direotly aotuated' hy the rising;` olf said lioat to close said vaeuuin connection, a valve lf'or Closing' said air vent. und means actuated hy the ditlierentinl oit :itriospherie and voeuuin pressure l'or controlline4 the alternate seating' and unseetingg oit the last mentioned valve.

ln :i vaouuin tankT a Compartment prod Jith a liquid supply oonneotioin a shot-lr valveeontrolled liquid discharge pas- Si [i sage and a Valve controlled air vent, of `a l'loat in seid compartment, a valve directly actuated by the rise of said float for cuttingl oli said Vacuum coi'mection, and means sul)- jeeted to differential preseure in the atmosphere andthe vacuum for resisting the rise of Said vfloat and closing oi? said vacuum valve, and means pneumatically operated on the overcoming of said resistance Yfor uuseating said air vent valve.

6. In a vacuum tank, an upper compartment and a lower compartment, the upper compartment being` provided with' a liquid supply connection, a vacuum connection, a valveecontrolled vent eoiniectlon and a check valve controlled liquid discharge, a float in said upper compartment, a 'valve actuating Said float 'for opening and closing said Vacuum connection, pneumatieally operated means controlled by said float for operating said air vyent Valve and a vent connection between the upper and lower compartment, a normally open valve controlling said vent adapted to loe closed hy the vacuum and automatically opening` on failure of vacuum.

7. ln a vacuum tank, a compartment provided with a liquid supply connection, a

vacuum connection, a discharge passage and an air vent port, oi a `float in said compartment, a valve aetuatedloy said float to close said vacuum connection, u, Valve for closing said air vent, a connection between said vaciunn connection and said air 'vent port, a gravity seated Valve in the last mentioned connection, and means for unseating said gravity seated Valve simultaneously with the seating of the first mentioned valve thereby causing the second mentioned Valve to become unseated.

8. ln a vacuum tank, an upper` compartment and a lower compartment, the upper compartment being; provided with a liquid supply eonnection, a vacuum connection, a valve-controlled 1vent connection, and a cher-l valve controlled liquid discharge, a' float in said upper compartment, a Valve actnated by Said i'loet for opening' and closing` seid vacuum connection, pneumatically opereted meane controlled by said loat for operating;l said air vent valve, and means for permitting;` the equalization of liquid levels in the two compartments.

ln testilnony whereof I al'lix my sigllature.

WILFRED 0. 'GHAS l. 

